Scope: Practical commentary on NEC4 ECC. Check the edition, selected options, Contract Data and amendments used on your project.
Identify the competing causes
Start with a chronology: what happened, when, which activities were affected and what prevented each activity from progressing. Separate the event itself from its effect on the programme.
Describe the Contractor-risk event and the alleged compensation event individually. Avoid deciding causation merely because the dates overlap or both events appear in a progress report.
Apply the NEC4 assessment process
Use the Accepted Programme relevant to the dividing date and apply the NEC4 ECC assessment provisions. Clause 63.5 addresses time effects. Where the clause 64 conditions apply, the Project Manager assesses the programme for remaining work for the assessment.
Do not substitute an assumed JCT outcome such as “time but no money”. Contract wording, amendments, facts and the analysis matter. A comparison with another form needs its own careful explanation.
NEC’s Practice Note 1.1 (January 2019) explains how the assessment recognises events between the Accepted Programme’s date and the dividing date, including events that are not compensation events. Keep these effects visible when isolating the effect of the compensation event under review.
Distinguish activity float and terminal float
Terminal float is the gap between planned Completion and the Completion Date. NEC4 ECC protects that gap for the Contractor in compensation event assessment. It should not be described as a shared buffer which a compensation event must exhaust before the Completion Date moves.
Float within an activity sequence is a different issue. Explain whether the affected work changes planned Completion, rather than referring loosely to “six weeks of float on the critical path”.
Make the analysis reproducible
Retain the programme version, progress status, logic changes and assumptions used in the assessment. Explain how the event affects the remaining work and why the identified activities control the outcome.
Time-impact analysis may be useful, but the label alone does not prove compliance with the contract or establish causation. The method must suit the evidence and the contractual assessment being performed.
Keep the evidence connected
- Preserve the Accepted Programme and relevant updates.
- Record access, instructions, resource availability and progress by location.
- Identify concurrent activities without assuming concurrent critical delay.
- Explain assumptions and test their effect on the result.
- Notify and respond under the contract while the analysis is developed.
Complex concurrency disputes may need specialist programming and legal input. Records improve the basis for analysis; they do not justify a predetermined allocation of delay.
Sources and further reading
- NEC: Accepted programmes
- NEC: Time risk allowances and terminal float
- NEC: Purposes of notifications
- GMH Planning/CECA: Clause 63.5 and the Accepted Programme (practical commentary; check the applicable contract and amendments).
Related GMH guidance and discussion
These are practical commentary and discussion. Check the NEC edition and project amendments; older posts may use earlier clause numbering.
.webp)
